Tire bead and method of making same



June 9, 1931. J. c. cARLlN TIRE BEAD AND METHOD OF MAKING SAME Filed Aug. lO. 1929 /NI/ENTOR J C; Carlin,

ATTORNEY Patented June 9, 1931 l UNITED STATES JAM'Eso. CARLIN, or GLADWYNE, PENNSYLVANIA, AssrGNoR ToLEE RUBBER a 'rims coNsHoHocKEN, PENNSYLVANIA, A CORPORATION 0F NEW CORPORATION, OF

YORK l lnxlarmA OFFICE TIRE BEAD AND METHOD F MAKING SAME Appiication inea August 1o, 192e.` serial No. 384,899.

This invention relates to the manufacture of inextensible bead cores and their incorporation in the edges of pneumatic tires, particularly in the so-called flat or drum-built 5 tire bands adapted to be expanded into tire shape.

It is generally necessary to combine a soft filler element with the flexible wire portion of the bead core, especially when using two or more turns of flat wire shape, said filler occupying the triangular space between the fabric plies at the apex of the core and serving to avoid a sawing action of the wire on the fabric during operation of the tire. The

wire tape is commonly coated with plastic rubber in a tubing machine before being wound on itself to make a ring.

In a drum-built tire, this soft filler is located at the inner edge of the wire element during the make-up of the tire band, and it becomes shifted to the top of said wire element when the beads are turned through an angle of approximately 90 degrees in shaping the band to tire form, the wire tape being shifted from a horizontal to a vertical plane. The practice heretofore has been to use a separately inserted iller, and the application of such filler to the wire, as well as the incorporation of the bead core elements in l the tire band, have presented some dillculties involving a relatively-high labor cost for this operation and often more or less defective workmanship.

The object of my invention is to overcome i 35 these difficulties, to decrease the labor cost by associating the filler as a unit with the wire strip before winding the latter into a ring, and to improve the quality of the product by minimizing the opportunities for .defec- H tive workmanship.

Of the accompanying drawings,

Fig. 1 is a cross-sectional perspective View of a portion of the plastic-covered wire bead strip having a filler strip formed thereon.

Fig. 2 is a cross-sectional perspective view of the bead ring composed of several turns of the composite strip wound up on itself.

Fig. 3 is a fragmentary sectional View of a drum-built tire-forming band having the bead ring of Fig. 2 incorporated therein.

Ywith the soft filler atthe .inner Fig. 4 is a fragmentary sectionalyiew of the edge of a shaped tire casing with lthe bead incorporated. `i

` Cross-hatching of the carcass and surface plies is omitted in Figs. 3 and 4 for the sake of clearness. i

Referring to Fig. 1, 10 is the usual flat bead strip of flexible wire strands,`fabricated yas by braiding or weaving, 11 is plastic,

vulcanizable rubber compound covering said strip vand filling its interstices, and 12 is a marginal strip of said compound ylocated at one edge of the wire strip and integral with the covering 11. In Fig. 2, several turns of the bead strip represented in Fig. 1 are shown wound one upon the other to make a bead core ring. yThe various plies of rubbei-ized carcass Vfabric are shown at 13, and 13 is the flipper or rubberized fabric covering for the b ead core. 14 is a tire-band building drum. As shown Vin Fig. et, when the'tire band is formed into tire shape and vulcanized, the several component filler strips 12 will have been shifted to the top side or outer periphery of the wire ring and consolidated in a liller 15 of triangular section filling the space at the apex of the bead core on the outer periphery of the wire ring. o.

The method of procedure is as follows: `The fabricated wire strip .10 making up the inextensible body of the beadcore is passed through a specially shaped die ina tubing machine Aand a coating of soft plastic rub- 'ber 11 is extruded thereon. The die Vis of such shape as to cause an excess `of the soft rubber to be extruded at one edge of the wire strip as indicated at 12 inFig.;` 1. n

The strip may be cut into desired lengths or leddirectly onto a drum orform where it is built into abend ring or grommet by winding two or more turns, one upon-the other, as shown in Fig. 2, the several component `Yiiller strips 12 collectivelyv` constituting a laminated soft filler at the edge of the laminated wire ring. i

The flipper strip 13a is next wrapped about the bea-d grommet, the flippered bead. core is applied to the .underlying carcass iplies edge ofthe wne ring, the outer carcassplies are wrapped li115 i 90' to assume the relative position shown in Fig. 4, the Wires being more or less shifted from a horizontal to avertical plane and the filler 15 being shifted-to theouter periphery of the Wire ring. Vulcanization of the tire casing is then effected to consolidate all of By simultaneously covering the Wire strip with plastic material and integrally forming an excess strip of said materialv on the edge of the Wire, thenlwinding the composite strip into a` ring and incorporating the bead core in the tire as described, my invention eliminates some troublesome steps in the y manufacture of bead cores and tires, which have been involved in theprior methodof separately applying the iller strip after the bead ring is made. The labor cost is thereby materially reduced and less skill is demanded on the part of the bead builders and tire builders iii attaining the desired quality of workmanship. p r Y I Claimz- 1. The method of makin tire bead cores which comprises covering a exible Wire strip With plastic material and simultaneously applying an additional soft filler. of said material to the edge of said strip. i

2. The method of making tire bead coi'es which comprises simultaneously covering a flexible Wire strip with plastic material, and uniting a softpfiller-forming margin of said material with the edge of said. strip, by extrusion. n 1 p j 3. The method of making a combined Wire bead'coi'e and filler which comprises covering a flexible Wire strip with plastic material,

` simultaneously forming an excess of said material into a plastic margin on the edge of said strip, and Winding rsaid strip upon itself as a ring having a laminated soft edging to constitute the bead filler. y

4. The method of making beads in drum- `built"tii'es which comprises producing a laminated ring of rubber-covered Wire tape having aflaminated rubber edging to form the bead filler, applying said ring, .With its kfiller` at the inner edge, tothe underlying carcass plies of a tii-e-formingband, wrapping tlie inner and outer carcass plies about covering being integrally extended at one edge to form a bead filler.

6. An intermediate product in the formation of tire beads which comprises a Wire strip having a soft edging, said strip being Wound upon itself and the several plies of the edo'ing collectively constituting a soft filler.

n Witness whereof I have hereunto set my hand this 7th day of August, 1929.

JAMES C, CARLIN.

saidring, expanding said band to tire shape v andtbringing thefillei' to the outer periphery of the Wire element. .p

" 5, A flat, fabricated Wire strip for bead cores having a 'plastic covering thereon, said lio 

